Error detection method of sheet holder and image forming apparatus using the same

ABSTRACT

According to one embodiment, an error detection device including a sensor which detects a state where an object has moved to a predetermined position, a drive device which drives the object to a predetermined position, and an error determination device which reports that a predetermined process is to be performed with respect to the target, if the sensor detects a state where the target does not move to the predetermined position within a predetermined time from if the drive device starts driving.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from: U.S. Provisional Application No. 61/326,585 filed on Apr. 21, 2010, the entire contents of each of which are incorporated herein reference.

FIELD

Embodiments described herein relates generally to an image forming apparatus and an error detection method of a sheet holder.

BACKGROUND

A toner (a visualizing agent) moves to a sheet medium on the basis of image information and is integrated with the sheet medium. The sheet medium (integrated with the toner) is a hard copy.

Conventionally, a sheet holder contains the sheet medium. Whenever an output of the hard copy is required, the sheet medium moves sheet by sheet from the sheet holder to a position to which the toner moves.

When containing “zero” sheet medium, the sheet holder reports “Empty”.

Also, when failing to detect the movement of the contained sheet medium to the position to which the toner moves, the sheet holder outputs an “Error message for jamming of deliver of the sheet medium”.

However, in some cases, the same “Error message” is output when a service (user support from a supplier) is necessary (a user cannot deal with an error) and when the service is not necessary (the user can deal with the error), since the number of required sensors is made to be a minimum in terms of cost in this situation (by the influence of the situation).

Accordingly, in a case where the “Error message” which requires a service is output even if the error does not require a service (the user can deal with the error) this causes a great disadvantage to the user.

BRIEF DESCRIPTION OF THE DRAWINGS

A general architecture that implements the various features of the embodiments will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments and not to limit the scope of the embodiments.

FIG. 1 is an exemplary diagram showing an example of an MFP, according to an embodiment;

FIG. 2 is an exemplary diagram showing an example of the MFP, according to an embodiment;

FIG. 3 is an exemplary diagram showing an example of a sheet holder of the MFP according to an embodiment;

FIG. 4 is an exemplary diagram showing an example of the sheet holder of the MFP according to an embodiment;

FIG. 5 is an exemplary diagram showing an example of the sheet holder of the MFP according to an embodiment;

FIG. 6 is an exemplary diagram showing an example of a sheet holder path of the MFP according to an embodiment;

FIG. 7 is an exemplary diagram showing an example of the sheet holder of the MFP, according to an embodiment;

FIG. 8 is an exemplary diagram showing an example of the MFP, according to an embodiment;

FIG. 9 is an exemplary diagram showing an example of the MFP, according to an embodiment;

FIG. 10 is an exemplary diagram showing an example of the MFP, according to an embodiment;

FIG. 11 is an exemplary diagram showing an example of the MFP, according to an embodiment;

FIG. 12 is an exemplary diagram showing an example of the MFP, according to an embodiment; and

FIG. 13 is an exemplary diagram showing an example of the MFP, according to an embodiment.

DETAILED DESCRIPTION

In general, according to an embodiment, an error detection device comprising: a sensor which detects a state where an object has moved to a predetermined position; a drive device which drives the object to a predetermined position; and an error determination device which reports that a predetermined process is to be performed with respect to the target, if the sensor detects a state where the target does not move to the predetermined position within a predetermined time from if the drive device starts driving.

Embodiments will now be described hereinafter in detail with reference to the accompanying drawings.

FIG. 1 schematically shows an MFP (Multi-Functional Peripheral) to which the embodiment is able to apply.

An MFP 101 includes an image forming section (a printer section) 1 for outputting image information as an output image which is referred to as a hard copy or a print out, a sheet feeder 3 to supply a sheet medium having an optional size, which is used for an image output, to the image forming section 1, and a scanner section 5 to provide image data of an original to the image forming section 1.

Moreover, the scanner section 5 integrally has an automatically-document feeder (ADF) 7 for feeding the original to a reading position on the scanner section 5.

A control panel 9 for giving an instruction for starting image formation in the image forming section 1 and starting to read image information of the original through the scanner section 5 is placed in a strut 9 a fixed to the image forming section 1 and a swing arm 9 b in a corner at a left or right side behind the scanner section 5.

In a large number of MFPs, the sheet feeder 3 includes two or more sheet holding devices, that is, cassettes 31.

Currently, in a large number of MFPs, the individual cassettes 31 (of the sheet feeder 3) can be connected to a finisher 103 to reduce an installation space required in the MFP 101 and to process the output hard copy and to an LCF (Large Capacity Feeder) 105 being capable of containing two times or more of the sheet media compared to two or more of the cassette. Therefore, each cassette 31 has a configuration in which the cassette moves forward (Z direction) when supplying the sheet media, for example.

In the MFP 101 shown in FIG. 2, the image forming section 1 includes first to fourth photoconductive drums 11 a to 11 d for holding latent images, developers 13 a to 13 d for supplying a toner to the latent images on the photoconductive drums 11 a to 11 d to develop toner images, a transfer belt 15 for holding the toner images transferred from the photoconductive drums 11 a to 11 d in order, cleaners 17 a to 17 d for cleaning the individual photoconductive drums 11 a to 11 d, a transfer roller 18 for transferring the toner image held by the transfer belt 15 onto a sheet medium, a fuser 21 for fixing the toner image transferred to the sheet medium by the transfer roller 18 onto the sheet medium, and an exposing device 23 for forming latent images on the photoconductive drums 11 a to 11 d.

The first to fourth developers 13 a to 13 d store toners having optional colors of Y (yellow), M (magenta), C (cyan) and Bk (black) which are used for obtaining a color image by a subtractive process and visualize the latent image held by each of the photoconductive drums 11 a to 11 d in any of the colors Y, M, C and Bk. The respective colors are determined in predetermined order corresponding to an image forming process or a characteristic of the toner.

The transfer belt 15 holds the toner images having the respective colors which are formed by the first to fourth photoconductive drums 11 a to 11 d and the corresponding developers 13 a to 13 d in order (of the formation of the toner images).

The sheet feeder 3 supplies the sheet medium to be transferred the toner image by the transfer roller 18.

Cassettes positioned in a plurality of cassette slots store sheet media having optional sizes. Depending on an image forming operation, a pickup roller 33 takes the sheet medium out of the corresponding cassette. The size of the sheet medium corresponds to a size of the toner image formed by the image forming section 1.

Each separating mechanism 35 prevents at least two sheet media from being taken out of the cassette by the pickup roller 33.

A plurality of delivery rollers 37 feed the sheet medium separated to be one sheet medium by the separating mechanism 35 toward an aligning roller 39.

The aligning roller 39 feeds the sheet medium to a transfer position in which the transfer roller 18 and the transfer belt 15 come in contact with each other in a timing for transferring the toner image from the transfer belt 15 by the transfer roller 18.

The fuser unit 21 includes a first roller 121 producing heat by the heat from a heater 129; a belt 127 receiving the heat from the first roller 121, hung over a second roller 123 and the first roller 121, and transferring the heat of the first roller 121 to the second roller 123; and a third roller 125 providing a predetermined pressure to the sheet medium which moves between the belt 127 and the third roller 125 while being adjacent to the belt 127.

An arbitrary portion of the belt 127 and an outer circumference of the third roller 125 form a nip by a pressure applied to the second roller 123 and the third roller 125. By this configuration, a predetermined pressure and a temperature (fixing temperature) by which the toner can be melted are applied to the sheet medium passing through the nip so that the toner (toner image) held by the sheet medium can be fixed.

The fuser 21 fixes the toner image corresponding to the image information onto the sheet medium as the output image (hard copy, print out) and feeds the output image to a stocker 47 positioned in a space between the scanner section 5 and the image forming section 1.

The fuser 21 includes a reversing roller 49. In an automatic duplex unit (ADU) 41 for replacing both sides of the sheet medium, the reversing roller 49 moves the sheet medium that has held the toner image corresponding to the image information to a reverse path 43 of the ADU 41, separately from the operation of moving the output image (hard copy and print out) to the stocker 47.

The ADU 41 moves to a side (a right side) with respect to the image forming section 1, if the sheet medium is jammed between the delivery roller 37 (a final one) and the aligning roller 39 or between the aligning roller 39 and the fuser 21, that is, in the transfer roller 18 or the fuser 21. The ADU 41 integrally has a cleaner 25 for cleaning the transfer roller 18.

FIG. 3 shows the characteristics of single cassette 31 in a state where the cassette is pulled out in the Z direction.

The cassette 31 includes a tray 31-2 holding the sheet media and turning on pivot points 31-2 a with respect to a bottom surface 31-1 a of a housing 31-1, and a pair of guides 31-3 setting a position in the Z direction of the sheet media held by the tray 31-2. The guides 31-3 restrain the change of the position (in the Z direction) of the sheet media in the tray 31-2. By the displacement of an open end (a free end opposite to the pivot points 31-2 a) 31-2 b of the tray 31-2 in a Y direction caused by a tray up unit 32 described later, the sheet media held by the tray 31-2 move to a direction adjacent to one of the pickup rollers 33.

By turning on the pivot points 31-2 a positioned at two points, the tray 31-2 pushes the sheet media up to the pickup roller 33.

Using the tray up unit 32 shown in FIG. 4, the tray 31-2 turns on the pivot points 31-2 a. As a thrust force for causing the displacement of the tray 31-2, the tray up unit 32 rotates a coupling 32 a shown in FIG. 5. For example, with a device that converts a rotational movement to a linear movement, such as a worm gear, the tray 31-2 moves to the Y direction according to the rotation that a shaft 31-2 c receives from the coupling 32 a. In this manner, the sheet media held by the tray 31-2 contacts the pickup roller 33 and the pickup roller 33 takes one of a state where a predetermined position or not positioned. Here, when the state of the predetermined position or not positioned of the pickup roller 33 is detected by a tray up detection switch described later with reference to FIGS. 6 and 7. Also, for example, by detecting a connection between the shaft 31-2 c and the coupling 32 a by using a cassette sensor 32 b near the coupling 32 a, it is possible to manage the movement of the cassette 31 in the Z direction (the movement of the sheet feeder 3 from a predetermined position) made to replenish the set sheet media.

A tray up detection switch 34 is positioned in a predetermined position near the pickup roller 33 at the side of the sheet feeder 3. The tray up detection switch 34 detects a state where the pickup roller 33 is in a position occupying a predetermined space with the moving of the tray 31-2. For example, when the tray 31-2 is displaced to a position shown in FIG. 7, and then the pickup roller 33 is positioned in the predetermined position, an output of the tray up detection switch 34 changes from H (High) to L (Low). The change in the output of the tray up detection switch 34 depends on the characteristics (design) of a control circuit. Therefore, when the pickup roller 33 is displaced to the position shown in FIG. 7, the output may also change from L (Low) to H (High).

FIG. 8 shows an example of a control system of the MFP 1 by focusing mainly on the tray up detection switch, the cassette sensor, and the tray up unit.

A control section 111 in a predetermined position in the MFP 1 includes a system bus 112.

The system bus 112 is connected to a main control block processing the output of the hard copy of the original performed by the image forming section 1, that is, a main control block (CPU) 113. The CPU (main control block) 113 is connected to the scanner (image reading) section 5, the ADF (automatically-document feeder) 7, and an operation unit 9. The control section 111 also includes an image processing section 141. The image processing section 141 is connected to the CPU 113 through the system bus 112 and performs an image process resulting from the request for forming an output image by the image forming section 1, on image data input from the scanner section 5 or a client (PC (Personal Computer)) 201 connected through a LAN (Local Area Network) controller 114.

The CPU 113 is also connected to a ROM (Read Only Memory) 115, a RAM (Random Access Memory) 116, and a non-volatile memory 117 storing the total number of images formed, the total operation time, or the like.

From an output of the cassette sensor 32 b connected to an I/O (input and output port and interface) 118, the CPU 113 detects a state where the arbitrary cassette 31 in the sheet feeder 3 is positioned (inserted) in a predetermined position, or, a state where the cassette moves (is drawn out) in the Z direction. Also, according to the change in the output of the tray up detection switch 34 connected to the I/O (input and output port and interface) 118, CPU 113 detects the operation failure of the tray up unit 32 (error detection). For example, the error detection includes a case where a tray up motor 132 of the tray up unit 32 (described later) is instructed to rotate, and the tray up detection switch 34 cannot detect the displacement of the tray 31-2 within a predetermined time has passed.

The CPU 113 controls, for example, the operation timing of motor drivers 131 a and 131 b which are connected to a sheet carriage control unit 130 in the sheet feeder 3 connected through the system bus 112. The motor driver 131 a drives the tray up motor 132 generating the thrust force for moving the tray 31-2 in the Y direction by operating the coupling 32 a in the tray up unit 32, and the motor driver 131 b drives a pickup motor 133 rotating the pickup roller 33 at a predetermined timing, the pickup roller 33 picking up the sheet media with the size corresponding to the size of the output image from each tray 31-2 (cassettes 31).

On a map of a connected page memory 142, the image processing section 141 creates output data (output image data) corresponding to an output image.

Incidentally, in a state where the tray up detection switch 34 cannot detect the displacement of the pickup roller 33 (tray 31-2) due to time-out or the like, a service (user support from the supplier) is necessary (since the user cannot deal with the error) or not necessary (since the user can deal with the error) depending on the situation.

An abnormality of the tray up unit 32, for example, the abnormality of the motor rotating the coupling 32 a, the disconnection of the line (electric wire) supplying the driving current and/or breakage of mechanism of rotating and driving requires a service.

However, even in the case that can be resolved by the simple check performed by the user, for example, in the case where the operation of the tray 31-2 is hindered since the guides 31-3 tightly abut on the sheet media to set the position of the sheet media in the Z direction, the tray up detection switch 34 detects an error as described above.

Accordingly, when the abnormality of the tray up unit 32 is detected, for example, by displaying an error message shown in FIG. 9 on a touch panel (display unit) 9A of the operation unit 9, and then requesting the user to simply check (encourage the user to perform a simple check) whether the service is necessary (user support from the supplier), it is possible to reduce the disadvantage that the user suffers due to waiting for the service. The message to be displayed is preferably a message showing the possibility of unusability such as “There is an error. It is possible to check if service is necessary in the following sequence”.

In more detail, as shown in FIGS. 10 to 12, a) a message encouraging the user to move the cassette 31 from a predetermined position (a position at the time of image formation) of the sheet feeder 3 in the Z direction and placing the sheet media in the replenishing position, is displayed on the touch panel (display unit) 9A of the operation unit 9 (FIG. 10). As an example of the display, it is preferable to display a message such as “There an error of carrying sheet from the cassette. Please draw the cassette out.” and/or to perform GI (graphical interface) display encouraging the user to carry out the operation.

Following the display for encouraging the movement of the cassette 31 in FIG. 10, after a predetermined time has passed, or at the point of time when the movement of the cassette 31 in the Z direction is detected by the cassette sensor 32 b, b) a message encouraging the user to remove the sheet media from the tray 31-2 is displayed on the touch panel (display unit) 9A of the operation unit 9 (FIG. 11). It is preferable to display a message such as “Please take out all sheets from the cassette” and/or to perform GI (graphical interface) display encouraging the user to carry out the operation.

Subsequently, after a predetermined time passes from the display encouraging taking out the sheet media in FIG. 11, c) a message encouraging the user to put the cassette 31 back to a predetermined position (the image formation position) of the sheet feeder 3 is displayed on the touch panel (display unit) 9A of the operation unit 9 (FIG. 12). It is preferable to display a message such as “Please put the empty cassette back in, all of sheet media are taken off” and/or to perform GI (graphical interface) display encouraging the user to carry out the operation.

When the cassette sensor 32 b detects the state where the user puts the cassette 31 containing “zero” sheet media back in the predetermined position of the sheet feeder 3 after the display for encouraging the user to perform the operations (processes) from a) to c) made on the touch panel (display unit) 9A of the operation unit 9, the tray up unit 32 moves the tray 31-2 to a predetermined position in the Y direction.

Hereinafter, when the output of the tray up detection switch 34 changes within a predetermined time, in order that the displacement of the tray 31-2 to a predetermined position occurs, the error detected by the tray up detection switch 34 is determined to be an error that the user can deal with without requiring the service.

In this case, on the touch panel (display unit) 9A of the operation unit 9, massages encouraging performing the process for continuously using the MFP 1 such as “Please draw out the cassette again, and set the sheet media” and “Please put the cassette set with the sheet media back to a predetermined position” are displayed at a predetermined timing.

When the cassette sensor 32 b can detect the state where the user “drew out the cassette again, set the sheet media, and put the cassette set with the sheet media back to a predetermined position” following the message, a message such as “The problem in setting the sheet media in the cassette is resolved thanks to your cooperation. Go ahead, and you can use the apparatus”, which expresses thanks for the cooperation and reports the fact that the MFP can be used is displayed.

Meanwhile, when the change in the output of the tray up detection switch 34 fails to be detected within a predetermined time even though the cassette sensor 32 b detects the state where the cassette 31 containing “zero” sheet media returns to a predetermined position of the sheet feeder 3 after completion of the operations (processes) from a) to c), and the tray up unit 32 is operated accordingly, the error detected by the tray up detection switch 34 is determined to be an error (an error that is difficult for the user to deal with) which requires the service.

In this case, on the touch panel (display unit) 9A, a message such as “An error which requires a service occurred. Please make an arrangement for the service”, which encourages the arrangement of the service and indicates that the continuous use of the cassette of the error is detected is difficult is displayed.

The above error includes:

-   -   [1] A problem in the tray up unit (damage, disconnection of the         driving power supply wire and/or breakage of mechanism of         driving), and     -   [2] An abnormal load is generated with respect to the tray or         sheet medium due to, for example,         -   [2a] The guide is tightly closed, or         -   [2b] There is a foreign substance on the tray or on the             sheet medium on the tray, so the tray cannot move to a             predetermined position, and         -   [2c] The number of the sheet media set in the tray exceeds             the allowable number. The case [1] is the “Error which             requires a service”.

For the case [2] ([2a], [2b], and [2c]), a description has been made (as above) in which the error is resolved by the checking operation performed by the user according to the above sequence.

That is, as shown in FIG. 13, in the standby state, by selecting an arbitrary cassette according to the selection of size, or, by inserting the cassette in the sheet feeder, the state of the tray up detection switch is checked [Act111]. When the tray up detection switch is turned “ON” [Act111-YES], the standby state where the normal operation (copy) is available is made [Act120].

When the tray up detection switch is not turned “ON” [Act111-NO], the tray up motor is rotated to start the tray up operation [Act112].

After the start of the tray up operation, when the output of the tray up detection switch changes to be “ON” within a prescribed time [Act113-YES], the standby state where the normal operation (copy) is available is made [Act120].

After the start of the tray up operation, when the output of the tray up detection switch does not become “ON” within a prescribed time [Act113-NO], the messages shown in FIGS. 9 to 12 and encouraging the user to perform the checking with respect to the tray up error are displayed in a display panel (touch panel) 9A of an operation unit 9 in order [Act114].

Thereafter, the state where the cassette returns to the inside of the sheet feeder is detected by the cassette sensor 32 b [Act115], and the tray up operation is started by rotating the tray up motor [Act116].

Following the tray up operation, when the output of the tray up detection switch does not become “ON” within a prescribed time [Act117-NO], it is determined that there is an abnormality in the tray up unit, and a message such as “An error which requires a service occurred. Please make an arrangement for the service”, which reports the tray up error is displayed in the display panel (touch panel) 9A of the operation unit 9 [Act118].

When the output of the tray up detection switch becomes “ON” within a prescribed time from the start of the tray up operation [Act117-YES], it is determined that the inappropriate setting of the sheet media onto the tray or the tray up error resulting from the foreign substance is resolved, and messages such as “There is a concern that the setting state of the sheet media in the cassette could be a factor of the error detection.” and “The problem in setting of the sheet media in the cassette is resolved thanks to your cooperation. Go ahead, and you can use the apparatus”, which report that the tray up error is resolved are displayed in the display panel (touch panel) 9A of the operation unit 9 [Act119].

In this manner, by requesting that the user perform the simple check (by encouraging the user to perform the simple check) regarding several error detection results accompanying the display of the error which does not necessarily require (the error which makes it difficult to determine whether the support is required) a service (user support), the arrangement for the service becomes unnecessary (the problem of waiting for the service is resolved) (by the simple check of the user) regarding the error that can be detected as the “error which does not require a service”.

For example, regarding the error which has possibility for detecting that the “error that does not require a service” by performing the simple check such as drawing out the cassette for which an error is displayed, taking out the sheet media, and inserting the cassette again, which does not impose a heavy burden to the user, it is easy to ask for the user's understanding since the burden becomes heavier if the user cannot use the MFP 1 due to waiting for a service.

In addition, the probability that the error detection itself makes an error (misdetection) decreases; hence the reliability is not lost.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. 

1. An error detection device comprising: a sensor which detects a state where an object has moved to a predetermined position; a drive device which drives the object to a predetermined position; and an error determination device which reports that a predetermined process is to be performed with respect to the target, if the sensor detects a state where the target does not move to the predetermined position within a predetermined time from if the drive device starts driving.
 2. The device of claim 1, further comprising: a display device which displays the content to be reported according to a result of determination performed by the error determination device.
 3. The device of claim 2, wherein the display device displays methods of counteracting with respect to the content to be reported according to the result of determination performed by the error determination device.
 4. A method to guide an error-counteracting comprising: detecting a state where there is no output of a sensor detecting a state where a target has moved to a predetermined position; and reporting a predetermined process is to be performed with respect to the object.
 5. The method of claim 4, further comprising: displaying a sequence for performing the predetermined process.
 6. A sheet medium supply device comprising: a tray which holds a sheet medium or sheet media; a detector which detects a state where the sheet medium and sheet media held by the tray are in a sheet medium supply position; a tray up device which moves the tray to hold the sheet medium or sheet media to the sheet medium supply position; and an error determination guide section which guides, if the detector to detect a state where the tray or a sheet picking up member is not in the sheet medium supply position within a predetermined time, a performance of a predetermined process for determining which is the factor causing such a state between the operation of the tray up device and the holding state of the sheet medium or sheet media held by the tray.
 7. The device of claim 6, further comprising: a display which displays a sequence to perform the predetermined process of carry out the determination encouraged by the error determination guide section.
 8. The device of claim 7, wherein the display to display a continuous process in order, on the basis of detection of the process corresponding to the sequence displayed by the error determination guide section.
 9. The device of claim 6, wherein, when a housing including the tray moves in a direction orthogonal to the direction in which the tray moves, the tray up device is disconnected from the drive device to move the tray.
 10. The device of claim 9, wherein the display displays continuous processes, if a state where the tray up device is connected to the drive device is detected.
 11. The device of claim 10, further comprising: a roller which moves the sheet medium or sheet media held by the tray to a predetermined position.
 12. The device of claim 11, wherein the tray up device moves the tray in a direction orthogonal to the direction in which the roller moves the sheet medium or sheet media.
 13. The device of claim 12, wherein the direction in which the housing including the tray moves includes a direction which is orthogonal to the direction in which the roller moves the sheet medium or sheet media and to the direction in which the tray moves, respectively.
 14. The device of claim 13, wherein a first process sequence displayed by the error determination guide section includes moving the housing including the tray in the movement direction of the housing.
 15. The device of claim 14, wherein a second process sequence displayed by the error determination guide section includes temporarily removing the sheet medium or sheet media held by the tray moved.
 16. The device of claim 15, wherein a subsequent process sequence displayed by the error determination guide section includes moving the housing including the tray from which the sheet medium or sheet media moved to a position where the tray up device is connected to the drive device.
 17. The device of claim 16, further comprising: a control unit detecting a state where the tray up device and the drive device are moved to a position in which they are connected to each other after the tray up device and the drive device are disconnected from each other, and performing the second movement of the tray caused by the tray up device.
 18. The device of claim 17, wherein, if the detector detects a state where the sheet medium or sheet media held by the tray are positioned in the sheet medium supply position, the control unit displays that there is an error caused by a factor which is the holding state of the sheet medium or sheet media held by the tray, on the display unit.
 19. The device of claim 17, wherein, if the detector detects a state where the sheet medium or sheet media held by the tray are not positioned in the sheet medium supply position, the control unit displays that there is an error caused by a factor which is the operation of the tray up device, on the display unit. 